function [s] = symbols(n)
% simple function to maintain symbols and symbol list
% 5/21/2000 P. Manis
% call: with n = nth argument
% returns structure s with s.s = symbol (s)
% s.f = fill (f)
% and s.c = color(c) with modulus on length
% of the lists here. That way you can add to the list easily
% Modified so that negative n yields a pairwise matching of symbols (e.g., grouped...)

% 
if(n > 0)
   symlist= {'o', 's', '^', 'd', 'o', 's', '^', 'd', 'o', 's', '^', 'd', 'o', 's', '^', 'd'};
	symfill= {'k', 'r', 'g', 'b', 'y', 'c', 'm', 'w', 'w', 'w', 'w', 'w', 'w', 'w', 'w', 'w'};
	symcolor={'k', 'r', 'g', 'b', 'y', 'c', 'm', 'k', 'k', 'r', 'g', 'b', 'y', 'c', 'm', 'k'};
else
   symlist= {'o', 'o', 's', 's', '^', '^', 'd', 'd', 'o', 'o', 's', 's', '^', '^', 'd', 'd', '*', '*', 'p', 'p'};
	symfill= {'k', 'w', 'r', 'w', 'g', 'w', 'b', 'w', 'y', 'w', 'c', 'w', 'm', 'w', 'k', 'w', 'r', 'w', 'g', 'w'};
	symcolor={'k', 'k', 'r', 'r', 'g', 'g', 'b', 'b', 'y', 'y', 'c', 'c', 'm', 'm', 'k', 'k', 'r', 'r', 'g', 'g'};
   n = -n;
end;   
nsym = length(symlist);
p = mod(n, nsym);
if(p == 0)
   p = nsym;
end;
s.s = char(symlist(p));
s.f = char(symfill(p));
s.c = char(symcolor(p));
return;
